Endoscopy is a medical procedure in which an instrument is used to examine and treat the interior of a patient's organ, usually through a natural orifice. For example, endoscopes are commonly used to examine or treat a hollow organ or cavity of the body, such as the stomach.
Endoscopy procedures have become useful for treating, among other things, pseudocysts. Over 80,000 people are diagnosed with pancreatitis in the United States annually. The condition typically results in acute upper abdominal pain and can be life threatening as the pancreas loses its endocrine and exocrine functions. In many cases, pancreatitis physically manifests itself as a pseudocyst, which is a fibrous collection of fluid formed atop the organ.
An effective treatment for the condition is through cyst drainage. Drainage of the cyst can be required if the cyst persists and or grows in size to be greater than five centimeters in diameter. Traditionally, pseudocysts have been treated surgically, requiring a large open incision through the stomach or with an endoscopic procedure.
Conventionally, endoscopic surgery was performed with a needle knife to make an incision into the stomach. Unfortunately, this procedure increased the risk for internal bleeding through the cutting of blood vessels. As a result, typical procedures now use a balloon to dilate the track instead. This procedure is known as cystgastrostomy. This change has resulted in endoscopic transmural drainage of pancreatic pseudocysts to become common as it makes use of a natural orifice, the mouth, instead of making an external incision through the stomach.
A cystgastrostomy is a minimally invasive procedure used to drain a pancreatic cyst accessed endoscopically via the stomach wall. After identifying a cyst via ultrasound, a first endoscopic instrument or accessory is used to provide a hollow needle. The hollow needle is guided by an endoscope containing a thin guidewire and used to puncture through the stomach wall to access the pancreatic cyst. A puncture location is determined by an endoscopic ultrasound based on trying to avoid blood vessels and to prevent bleeding.
The current cystgastrostomy methods, however, require the full removal of the needle along the guidewire before the balloon can be positioned in the incision. The first instrument or accessory with the needle is removed and the conventional procedure requires leaving the guidewire at the site of the cyst.
Using a second endoscopic instrument or accessory, a surgical balloon is then fed along the guidewire. The balloon is used to dilate the incision. The balloon is then deflated and also removed along the guidewire.
Fluid from the cyst drains into the stomach through a natural pressure gradient. Two to three pigtail stents may be inserted to facilitate the drainage. The stents can be left in place for a few days and removed at a later time. The efficacy of the drainage is assessed during a post-op to ensure there is no infection from clogging of the stents.
As noted, the conventional methods and instruments require the full removal of the needle tip along the guidewire and the subsequent insertion of a balloon along the same guidewire. This requires an exchange of endoscopic instruments or accessories. In this exchange, there exists a relatively high level of risk of guidewire dislocation from the pancreatic cyst access site. Such a loss of access is a considerable setback during this procedure because a gastroenterologist is then forced to either relocate the incision, or repeat the echo ultrasound to determine another acceptable puncture location. Having to find a new location only increases the risk of a hemorrhage.
Accordingly, it may be desirable to improve the conventional endoscopic procedures, such as those mentioned above.